PHYS 207 FINAL iClicker & Concept Questions (ch.10,16,17,12,13)

The graph shows the vertical displacement as a function of time at one location in a medium through which a wave is traveling. What is the period of the wave?

1.0 s

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing What is the angular frequency?

1.57 rad/s

The frequency of the longitudinal standing wave shown in the drawing is 440 Hz. The tube is open at both ends. What is the fundamental frequency of the tube

220 Hz

According to the Principle of Superposition, how are two waves combined to produce a resultant wave?

The amplitudes of the two waves are added algebraically

You are riding a bicycle along the side of a road when an ambulance comes up behind you with its siren on. As the ambulance passes, you notice that the sound of the siren changes. How does it change AFTER it passes you?

The frequency decreases to a lower frequency

A piano is tuned by tightening or loosing the piano wires. When the wires are tightened, how is frequency of the waves on the wire affected, if at all?

The frequency is increased

Complete the following statement: In general, the term stress or pressure refers to

a force per unit area

Complete the following statement: The term heat most accurately describes

the flow of energy resulting from a temperature difference

The sound intensity level is reported in decibels. If the sound intensity is at the threshold for hearing, what is the sound intensity level in decibels?

zero dB

What is the distance between the center of a condensation and the center of an adjacent rarefaction in a sound wave of wavelength λ?

λ/2

Two different objects are supplied with equal amounts of heat. Which one or more of the following statements explain why their temperature changes would not necessarily be the same?

- The objects are made from the same material but have different masses. - The objects have the same mass but are made from materials that have different specific heat capacities.

An 0.80-kg object is attached to one end of a spring, as in the figure, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the amplitude?

.08 m

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the speed at t = 1 s?

0 m/s

Suppose you have a simple pendulum that, on earth, has an angular frequency of 0.20 rad/s. What is its frequency on the moon, where gmoon=1/6gearth

0.08 rad/s

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the magnitude of the force on the object at t = 1 s?

0.16 N

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the magnitude of the object's acceleration at t = 1 s?

0.20 m/s2

Determine the length of a simple pendulum that will swing back and forth in simple harmonic motion with a period of 1.00 s

0.25 m

A longitudinal standing wave is established in a tube open at only one end (see the drawing). The frequency of the standing wave is 660 Hz, and the speed of sound in air is 343 m/s. What is the length of the tube?

0.39 m

Sound travels from a loudspeaker to your ear. If the sound frequency is 775 Hz, what is the wavelength of the wave? Take the speed of sound to be 343 m/s

0.443 m

What is the wavelength λ of a wave that has a speed of 160 m/s and a period of 0.004 s?

0.64 m

Two transverse standing waves are shown in the drawing. The wavelength of the standing wave at the top is 1.2 m. What is the wavelength of the one at the bottom?

0.8 m

A longitudinal standing wave is established in a tube that is open at both ends (see the drawing). The length of the tube is 0.80 m. What is the wavelength of the waves that make up the standing wave?

0.80 m

The drawing shows four moving pulses. Although shown as separated, the four pulses exactly overlap each other at the instant shown. Which combination of these pulses would produce a resultant pulse with the highest peak and the deepest valley at this instant?

1 and 2

The drawing shows four moving pulses. Although shown as separated, the pulses may exactly overlap each other at the instant shown. Which combination of these pulses would produce a horizontal straight line at this instant?

1 and 4

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the spring constant?

1.97 N.m

If the speed of sound is 340 m/s, the two lowest frequencies of an 0.5 m organ pipe, closed at one end, are approximately

170 Hz and 510 Hz

A 0.42-kg block is attached to the end of a horizontal ideal spring and rests on a frictionless surface. The block is pulled so that the spring stretches for 0.02 m relative to its unstrained length. When the block is released, it moves with an acceleration of 9.0 m/s2 . What is the spring constant of the spring?

189 N/m

The emissivity e of object B is 1/16 that of object A, although both objects are identical in size and shape. If the objects radiate the same energy per second, what is the ratio TB/TA of their Kelvin temperatures?

2

Five simple pendulums are shown in the drawings. The lengths of the pendulums are drawn to scale, and the masses are either m or 2m, as shown. Which one has the smallest angular frequency of oscillation?

2 m

The ends of a cylindrical steel rod are maintained at two different temperatures. The rod conducts heat from one end to the other at a rate of 10 cal/s. At what rate would a steel rod twice as long and twice the diameter conduct heat between the same two temperatures?

20 cal/s

Four standing wave segments, or loops, are observed on a string fixed at both ends as it vibrates at a frequency of 240 Hz. What is the fundamental frequency of the string

240 Hz/4 = 60 Hz 60 Hz

Which one of the following temperatures is approximately equal to the typical temperature of a classroom?

293 K

In a half-hour, a 65-kg jogger can generate 8.0x105J of heat. This heat is removed from the body by a variety of means, including the body's own temperature-regulating mechanisms. Consider the body of the jogger has a specific heat capacity of 3500 J/kg.C°. If the heat were not removed, how much would the body temperature increase?

3.5 C°

A 0.42-kg block is attached to the end of a horizontal ideal spring and rests on a frictionless surface. The block is pulled so that the spring stretches for 0.02 m relative to its unstrained length. When the block is released, it moves with an acceleration of 9.0 m/s2. What is the magnitude of the restoring force that the spring applies to go back into its unstrained position?

3.78 N

The graph shows the vertical displacement as a function of time at one location in a medium through which a wave is traveling. What is the amplitude of the wave?

4 m

An 0.80-kg object is attached to one end of a spring, as in figure 10.5, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing. What is the period of the simple harmonic motion?

4 s

The intensity a distance r from a spherically symmetric sound source is 100 W/m2. What is the intensity at five times this distance from the source?

4.0 W/m2

A transverse wave on a string has an amplitude A. A tiny spot on the string is colored red. As one cycle of the wave passes by, what is the total distance traveled by the red spot?

4A

Suppose a gold ring at T=70°C is dropped into a cup of tea at T=98°C. What is true of the temperature when thermal equilibrium is achieved? Assume that the process occurs inside an insulated container so that no energy is lost to the environment.

70°C < T < 98°C

A sound wave is generated in a tube that has one closed end. Which one of the following statements is FALSE?

A node occurs at the open end

The following three hot samples have the same temperature. The same amount of heat is removed from each sample. Which one experiences the smallest drop in temperature, and which one experiences the largest drop? Sample A: 4.0 kg of water [c = 4186 J/(kg·C°)] Sample B: 2.0 kg of oil [c = 2700 J/(kg·C°)] Sample C: 9.0 kg of dirt [c = 1050 J/(kg·C°)]

A smallest and B largest

Which one of the following statements concerning waves is FALSE?

A wave carries particles of its medium from one place to another

Two bars are conducting heat from a region of higher temperature to one of lower temperature. The bars have identical lengths and cross-sectional areas, but are made from different materials. In the drawing they are placed in "parallel" between the two temperature regions arrangement A, while they are placed end-to-end in arrangement B. In which arrangement is the heat conducted the greatest?

Arrangement A

Three cubes are made from the same material. As the drawing indicates, they have different sizes and temperatures. Rank the cubes according to the radiant energy they emit per second, largest first.

B, A, C

The heat conducted through a bar depends on which of the following? A. The coefficient of linear expansion B. The thermal conductivity C. The specific heat capacity D. The length of the bar E. The cross-sectional area of the bar

B, D, and E

The spring constant of the spring is 320 N/m and the bar indicator extends 2.0 cm. What force does the air in the tire apply to the spring?

Fx Applied = kx (320 N/m)(0.020 m)=6.4 N 6.4 N

Some animals have hair strands that are hollow, air-filled tubes. Others have hair strands that are solid. Which kind, if either, would be more likely to give an animal an advantage for surviving in very cold climates?

Hollow air-filled

A simple pendulum consists of a ball of mass m suspended from the ceiling using a string of length L. The ball is displaced from its equilibrium position by a small angle and released. Which one of the following statements concerning this situation is correct?

If the length of the pendulum were increased, the angular frequency of the pendulum would decrease.

Which one of the following statements concerning periodic waves is false?

If the periodic wave is traveling on a guitar string, its speed depends on the amplitude of the wave.

What is the difference between transverse and longitudinal waves?

In a transverse wave the disturbance always occurs perpendicular to the direction in which the wave travels, whereas in a longitudinal wave the disturbance always occurs parallel to the line of travel of the wave.

If you want to decrease the frequency of a simple pendulum by a factor of two you should ...

Increase the length by a factor of four

A ball of mass m is attached to the end of a spring that has a spring constant k. When the ball is displaced from its equilibrium position and released, it moves in simple harmonic motion. Consider the relationship between the angular frequency, the mass, and the spring constant you just studied. Which one of the following statements concerning that relationship is true?

Increasing the spring constant causes the angular frequency to increase.

The drawing shows an object attached to an ideal spring, which is hanging from the ceiling. The unstrained length of the spring is indicated. For purposes of measuring the height h that determines the gravitational potential energy, the floor is taken as the position where h = 0 m. The equilibrium position at which the object hangs stationary is identified as position 2. The object is set into vertical simple harmonic motion between positions 1 and 3. Identify the positions where the kinetic energy KE, the elastic potential energy EPE, and the gravitational potential energy GPE each have their maximum values during an oscillation cycle.

KE has a maximum value at position 2. EPE has a maximum value at position 3. GPE has a maximum value at position 1.

Which one of the following statements best describes the concept of sound intensity?

Sound intensity is the sound power that passes perpendicularly through a surface divided by the area of that surface

An object that obeys Hooke's law is displaced a distance x by a net force 𝐹. Which one of the following statements correctly describes the resulting acceleration of the object?

The acceleration increases as x increases and it decreases as x decreases.

A block of mass M is attached to one end of a spring that has a spring constant k. The other end of the spring is attached to a wall. The block is free to slide on a frictionless floor. The block is displaced from the position where the spring is neither stretched nor compressed and released. It is observed to oscillate with a frequency f. Which one of the following statements is true concerning the motion of the block?

The block's acceleration is greatest when the mass has reached its maximum displacement.

A block is hung vertically at the end of a spring. When the block is displaced and released, it moves in simple harmonic motion. Which one of the following statements is true concerning the block?

The maximum acceleration of the block occurs when its velocity is zero.

An astronaut has two objects that are identical in all respects, except that one is painted black and the other is painted silver. Initially, they are at the same temperature. When taken from inside the Space Shuttle and placed in outer space, which object, if either, cools down at a faster rate?

The object painted black.

You have two springs. One has a greater spring constant than the other. You also have two objects, one with a greater mass than the other. Which object should be attached to which spring, so that the resulting spring-object system has the greatest possible period of oscillation?

The object with the greater mass should be attached to the spring with the smaller spring constant

Two objects are made from the same material but have different masses. The two are placed in contact, and neither one loses any heat to the environment. Which object experiences the temperature change with the greater magnitude, or does each object experience a temperature change of the same magnitude? Assume the initial temperatures of the objects are different.

The object with the smaller mass experiences the temperature change with the greater magnitude

A particle of dust is floating in the air approximately one half meter in front of a speaker. The speaker is then turned on produces a sound of frequency 226 Hz. The sound waves produced by the speaker travel horizontally. Which one of the following statements correctly describes the subsequent motion of the dust particle, if any?

The particle of dust will oscillate left and right with a frequency of 226 Hz.

A wave moves at a constant speed along a string. Which one of the following statements is false concerning the motion of particles in the string?

The particle speed is constant

An object is in simple harmonic motion. The rate at which the object oscillates may be described using the period T, the frequency f, and the angular frequency w. If the angular frequency decreases, what is the effect on the period and the frequency?

The period would increase, but the frequency would decrease

On a warm spring day, you are waiting at a red traffic light listening to your favorite radio station with the windows down. The driver in a car passing you in the left turn lane at a constant speed happens to be listening to the same radio station. What do you notice as the car approaches and passes you?

The sound from the passing car seems to be at a higher frequency when approaching and at a lower frequency when moving away compared to the sound from your radio

Which one of the following statements is the definition of the specific heat capacity of an object?

The specific heat capacity is the amount of energy per unit mass to raise the temperature of the object by 1 C°

A piano is tuned by tightening or loosening the piano wires. When the wires are tightened, how is speed of the waves on the wire affected, if at all?

The speed is increased

Suppose 1000 J of heat were added to each of two 1.0-kg spheres originally at a temperature of 25.0°C. One sphere is composed of lead (c=128 J/(kg·K)) and the other of aluminum (c=9.00×102 J/(kg·K)). Which statement is true?

The temperature of the lead sphere increases by more than that of the aluminum sphere.

A small-amplitude transverse wave is traveling on a string. The frequency of the wave is suddenly doubled. Which one of the following is a true statement?

The wavelength is cut in half.

A string has one end attached to a wall and the other end attached to a motor that moves the end up and down in simple harmonic motion. The frequency of the motor is varied until a transverse standing wave is produced on the string that has four nodes. Which of the following statements concerning this situation is FALSE?

This standing wave represents the 4th harmonic.

A poker used in a fireplace is held at one end, while the other end is in the fire. In terms of being cooler to the touch, should a poker be made from (a) a high-thermal-conductivity material, (b) a low-thermal-conductivity material, or (c) can either type be used?

a low-thermal-conductivity material

Consider the graph shown for the position of a ball attached to a spring as it oscillates in simple harmonic motion. At which of the following times is the ball at its equilibrium position?

at 0 s, 4 s, and 8 s

An echo is sound that returns to you after being reflected from a distant surface (e.g., the side of a cliff). Assuming that the distances involved are the same, an echo under water and an echo in air return to you _____________________

at different times, the echo under water returning more quickly.

Complete the following sentence: The Principle of Linear Superposition may

be applied to all types waves

infrasonic

below 20 Hz

As the amplitude of a sound wave in air decreases to zero, _________________

both the condensations and the rarefactions of the wave disappear.

The wings of a soaring eagle are fully spread, but not moving. As the eagle glides through the air, it's also gaining altitude. Which one of the three methods of heat transfer is responsible for this gain in altitude?

convection

An object on a spring is oscillating in simple harmonic motion. Suddenly friction appears and causes the energy of the system to be dissipated. The system now exhibits ____________

damped harmonic motion

A block on a frictionless surface is attached to a horizontal spring that is stretched and released. Complete the following statement: The work done by the spring on the block

depends on the distance the spring is stretched from its relaxed position

Which of the following occurs when the Doppler effect is produced by a moving source of sound?

frequency changes

Which one of the following units is used for frequency?

hertz

ultrasonic

higher than 20 Hz

The drawing shows a composite slab consisting of three materials through which heat is conducted from left to right. The materials have identical thicknesses and cross sectional areas. Rank the materials according to their thermal conductivities, largest first.

k3, k2, k1

Which one of the following factors is most important in determining the speed of waves on a string?

mass per unit length

A standing wave is produced in a vertical tube with both ends open. Complete the following sentence: Inside the tube, air molecules are

moving up and down about their undisturbed positions.

Drawings show plots of displacement x versus time t for three objects undergoing simple harmonic motion. Which object has the highest maximum velocity?

object II

What is the distance between two successive antinodes of a standing wave?

one-half wavelength

An object in simple harmonic motion is observed to move between a maximum position and a minimum position. The minimum time that elapses between the object being at its maximum position and when it returns to that maximum position is equal to which of the following parameters?

period

The transfer of heat by convection is smallest in (a) solids, (b) liquids, (c) gases.

solids

Two cubes, one silver and one iron, have the same mass and temperature. A quantity Q of heat is removed from each cube. Which one of the following properties causes the final temperatures of the cubes to be different?

specific heat capacity

Two strings have the same mass and the same length. The tension in string 1 is three times the tension in string 2, however. The speed of a transverse wave on string 1 is ________ times the speed of a transverse wave on string 2.

square root of 3

Complete the following statement: The term heat most accurately describes

the flow of energy due to a temperature difference

Several days after a snowstorm, the outdoor temperature remains below freezing. The roof on one house is uniformly covered with snow. On a neighboring house, however, the snow on the roof has completed melted. Which house is better insulated?

the one covered with snow

Complete the following sentence: Destructive interference occurs when

two or more waves are present at the same place and the resultant disturbance has zero amplitude.

A certain dog whistle simultaneously emits a range of frequencies above 50 kHz. How can this sound be characterized?

ultrasonic

The drawing shows a graph of displacement x versus time t for simple harmonic motion of an object on a horizontal spring. Which one of the following answers correctly gives the magnitude v of the velocity and the magnitude a of the acceleration at points A and B in the graph?

vA = maximum, aA = 0 m/s2, vB = 0 m/s, aB = maximum

The units of heat are equivalent to those of which one of the following quantities?

work